bpf: selftests: Test constant key extraction on irrelevant maps

Test that very high constant map keys are not interpreted as an error
value by the verifier. This would previously fail.

Acked-by: Ed

bpf: selftests: Test constant key extraction on irrelevant maps

Test that very high constant map keys are not interpreted as an error
value by the verifier. This would previously fail.

Acked-by: Eduard Zingerman <[email protected]>
Signed-off-by: Daniel Xu <[email protected]>
Link: https://lore.kernel.org/r/c0590b62eb9303f389b2f52c0c7e9cf22a358a30.1738689872.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <[email protected]>

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bpf: selftests: verifier: Add nullness elision tests

Test that nullness elision works for common use cases. For example, we
want to check that both constant scalar spills and STACK_ZERO functions.
A

bpf: selftests: verifier: Add nullness elision tests

Test that nullness elision works for common use cases. For example, we
want to check that both constant scalar spills and STACK_ZERO functions.
As well as when there's both const and non-const values of R2 leading up
to a lookup. And obviously some bound checks.

Particularly tricky are spills both smaller or larger than key size. For
smaller, we need to ensure verifier doesn't let through a potential read
into unchecked bytes. For larger, endianness comes into play, as the
native endian value tracked in the verifier may not be the bytes the
kernel would have read out of the key pointer. So check that we disallow
both.

Signed-off-by: Daniel Xu <[email protected]>
Link: https://lore.kernel.org/r/f1dacaa777d4516a5476162e0ea549f7c3354d73.1736886479.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <[email protected]>

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selftests/bpf: Don't mask result of bpf_csum_diff() in test_verifier

The bpf_csum_diff() helper has been fixed to return a 16-bit value for
all archs, so now we don't need to mask the result.

This

selftests/bpf: Don't mask result of bpf_csum_diff() in test_verifier

The bpf_csum_diff() helper has been fixed to return a 16-bit value for
all archs, so now we don't need to mask the result.

This commit is basically reverting the below:

commit 6185266c5a85 ("selftests/bpf: Mask bpf_csum_diff() return value
to 16 bits in test_verifier")

Signed-off-by: Puranjay Mohan <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Reviewed-by: Toke Høiland-Jørgensen <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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selftests/bpf: populate map_array_ro map for verifier_array_access test

Two test cases:
- "valid read map access into a read-only array 1" and
- "valid read map access into a read-only array 2"

Exp

selftests/bpf: populate map_array_ro map for verifier_array_access test

Two test cases:
- "valid read map access into a read-only array 1" and
- "valid read map access into a read-only array 2"

Expect that map_array_ro map is filled with mock data. This logic was
not taken into acount during initial test conversion.

This commit modifies prog_tests/verifier.c entry point for this test
to fill the map.

Fixes: a3c830ae0209 ("selftests/bpf: verifier/array_access.c converted to inline assembly")
Signed-off-by: Eduard Zingerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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selftests/bpf: fix __retval() being always ignored

Florian Westphal found a bug in and suggested a fix for test_loader.c
processing of __retval tag. Because of this bug the function
test_loader.c:do

selftests/bpf: fix __retval() being always ignored

Florian Westphal found a bug in and suggested a fix for test_loader.c
processing of __retval tag. Because of this bug the function
test_loader.c:do_prog_test_run() never executed and all __retval test
tags were ignored.

If this bug is fixed a number of test cases from
progs/verifier_array_access.c fail with retval not matching the
expected value. This test was recently converted to use test_loader.c
and inline assembly in [1]. When doing the conversion I missed the
important detail of test_verifier.c operation: when it creates
fixup_map_array_ro, fixup_map_array_wo and fixup_map_array_small it
populates these maps with a dummy record.

Disabling the __retval checks for the affected verifier_array_access
in this commit to avoid false-postivies in any potential bisects.
The issue is addressed in the next patch.

I verified that the __retval tags are now respected by changing
expected return values for all tests annotated with __retval, and
checking that these tests started to fail.

[1] https://lore.kernel.org/bpf/[email protected]/

Fixes: 19a8e06f5f91 ("selftests/bpf: Tests execution support for test_loader.c")
Reported-by: Florian Westphal <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]/T/
Signed-off-by: Eduard Zingerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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selftests/bpf: verifier/array_access.c converted to inline assembly

Test verifier/array_access.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <[email protected]>

selftests/bpf: verifier/array_access.c converted to inline assembly

Test verifier/array_access.c automatically converted to use inline assembly.

Signed-off-by: Eduard Zingerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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